Move Bio-Formats downloads page under the main repository

- Convert Bio-Formats downloads page into Sphinx format. Page can be generated
as usual with `make html` and sphinx_theme can be applied as for the regular
Bio-Formats documentation.
- Add release download page build as part of the Travis build
Fix indents in index.html
Remove develop-specific artifacts
Revert "docs: whats-new: 1.6 is the minimum supported java version"

This reverts commit c1e48d5cd3f008f3246d378e9ccaf8debea1916f.
Merge pull request #653 from rleigh-dundee/java6-minver-dev_4_4

Make JDK 1.6 the minimum supported version (dev_4_4)
Merge pull request #680 from melissalinkert/cellworx-missing-tiff

CellWorx: do not assume that the first well/field file exists
Merge pull request #672 from melissalinkert/rebased/dev_4_4/11100

AVI: fix array index calculation for tile reading (rebased onto dev_4_4)
Merge pull request #622 from ctrueden/slf4j-version-dev_4_4

Upgrade SLF4J to 1.7.2 [dev_4_4]
Fix usage of tilde for Matlab versions earlier than R2009b
Drop typecasting workaround for Matlab versions earlier than 7.1
Add note about minimum supported version of MATLAB in the documentation
Re-expose the OME editor artifacts in the component table
ND2Handler: parse numbers defensively

Several numerical parsing methods throw NumberFormatException when
the input string is not actually a number. In particular:

* Integer.parseInt(String)
* Double.parseDouble(String)
* new Integer(String)
* new Double(String)

The ND2 handler parses a large number of string key/value pairs,
converting values into numbers in many cases. But in almost every case,
no error handling was done in case the input value was not a number.

This change adds a blanket try/catch for NumberFormatException around
areas that parse lots of numbers, emitting a warning for any
non-conforming key/value pairs. This allows parsing to continue,
hopefully resulting in a less fragile ND2 reader.

Note that this change is nearly all whitespace indentation; the easiest
way to view the "real" change is using "git show -b" on the commit.
merge dev_4_4 -D org -I include -E exclude: PR 673 (Make configuration file suffix configurable)
merge dev_4_4 -D org -I include -E exclude: PR 688 (Fix bfGetReader for Matlab R2009a and earlier)
merge dev_4_4 -D org -I include -E exclude: PR 690 (Bio-Formats downloads page (rebased onto dev_4_4))
merge dev_4_4 -D org -I include -E exclude: PR 691 (ND2 defensive parsing)